U.S. Pat. No. 4,476,524 (P09-80-009) uses real addressing of pages in main storage (MS) and in page store (PS) to asynchronously copy pages of data between MS and PS under control of a channel processor. A CP initiates the page transfer by executing a SIO (start input output) instruction which initiates a channel program comprised of channel control words (CCWs). U.S. Pat. No. 4,476,524 cannot use virtual addresses to move pages, and virtual addressing cannot be asynchronously forced into its method of operation. The subject invention does not use any real address in channel program CCWs to address pages.
U.S. Pat. No. 4,476,524 uses the real address within one of the two CCWs used per page to address the page. In U.S. Pat. No. 4,476,524 the first of the two CCW is either a PPI (prepare page in) or a PPO (prepare page out), and the second CCW is a page copy CCW in a variable chain of CCWs initiated by a SIO instruction. The CP may execute other instructions at the same time that the channel program is controlling the PS/MS page transfer of a variable number of pages. U.S. Pat. No. 4,476,524 does not disclose any move specification block (MSB), which is introduced by the subject invention for enabling virtual addressing in a CCW program.
European application 0 214 870 of Fujitsu (priority Feb. 9, 1985) describes and claims a synchronous page move instruction that operates on the central processor of a system. It is operand media dependent, i.e. it has an MS operand and an ES operand; while the subject invention is not media dependent among the media for which it is designed. This application does not disclose any MSB, introduced by the subject invention for enabling virtual addressing in a CCW program.
U.S. patent application Ser. No. 07/424,797, (PO9-89-018) filed Oct. 20, 1989, now U.S. Pat. No. 5,237,668 discloses a move page MVPG synchronous instruction which moves a single page and the central processor cannot execute any other instructions until the page move is completed. This application does not disclose any MSB, introduced by the subject invention for enabling virtual addressing in a CCW program and only moves a single page at a time.